1. Field of the Invention
This invention relates to methods of treating thrombosis, and more particularly to the use of magnesium to prevent conditions such as in-stent thrombosis.
2. Discussion of the Related Art
Coronary artery disease is one of the country's largest health concerns. According to the American Heart Association, this disease affects 13.5 million Americans. Almost a million of these people have experienced heart attacks. Still others have experienced angina, undergone coronary artery bypass surgery and/or had heart transplants. Others in the later, or more severe, stages of coronary artery disease are in varying stages of congestive heart failure.
Coronary artery disease, which has been linked with the increase in cholesterol and saturated fat in our diets, is treatable. One main symptom of coronary artery disease is the deposit of these fatty materials alongside a vessel wall such as an arterial wall. This results in the progressive narrowing of the lumen, and arteriosclerosis. Such deposits may be treated through a procedure called angioplasty. During angioplasty, the doctor inserts a catheter into an artery, typically a groin artery, and maneuvers the catheter up through the artery until the catheter is positioned at the site of the narrowing or obstruction caused by plaque. The plaque may then be flattened by inflating a balloon located around the tip of the catheter. As the balloon expands, it compresses the fatty deposits against the walls of the artery.
During this potentially lifesaving procedure, the doctor may insert a stent into the vessel at the site of the blockage. This small, typically metallic device helps to hold the vessel open and improves blood flow. This serves to relieve the symptoms of Coronary Artery Disease.
Unfortunately, stents do not provide an absolute solution to this problem. Restenosis, a narrowing of the passageway which may initiated by platelet adhesion and aggregation at the site of arterial injury, and thrombosis frequently occur at the site of the stent. “Thrombosis” describes the formation of a thrombus, or blood clot, inside a blood vessel. Thrombosis may be caused by the continuous stresses from blood flow over the stent. The longitudinal lumen of a stent usually, if not always, has an irregular surface or regions that protrude into the lumen that can produce a turbulent fluid flow. Alternatively, the thrombosis may be the result of a foreign body reaction to the stent. The formation of a blood clot within a blood vessel may cause tissue damage. Such a clot may be life threatening, particularly when it partially or completely blocks the flow of blood through a blood vessel. If thrombosis occurs as a result of the stent placement, a secondary procedure or a surgical bypass operation is required.
Products such as aspirin, dipyridamole and heparin are known in the art to dissolve such clots. While these products may eliminate the clot, they have the potential serious side effect of causing prolonged bleeding. Additionally, the effect of the administration of such products may only be reversed by the formation or addition of new platelets.
It is desired to be able to place a stent within a vessel through percutaneous transluminal delivery without the risk of in-stent thrombosis. Such stent placement without the risk of in-stent thrombosis would greatly increase the quality of life for many patients. Accordingly, a method to prevent the formation of in-stent thrombosis that is not detrimental to the patient is desired.